Question

我正在使用Codename One开发iOS应用。我扩展了SocketConnection类，以便从服务器接收数据。

class CustomSocketConnection extends SocketConnection {

    private OutputStream os;
    private InputStream is;
    private InputStreamReader isr;
    private String rawMessage;

    public CustomSocketConnection(){
        os = null;
        is = null;
        isr = null;
        rawMessage = null;
    }

    public synchronized String getRawMessage(){
        return rawMessage;
    }

    @Override
    public void connectionError(int errorCode, String message) {
        rawMessage = null;
        ToastBar.showErrorMessage("Error Connecting. ErrorCode: " + errorCode + " Message: " + message);
        System.out.println(">>>CustomSocketConnection, connectionError. Error Connecting. ErrorCode: " + errorCode + " Message: " + message);
    }

    @Override
    public void connectionEstablished(InputStream is, OutputStream os) {
        System.out.println(">>>CustomSocketConnection, connectionEstablished");

        char termination = '\n';

        int length = 1024;
        char[] buffer = new char[length];
        byte[] bufferByte = new byte[length];
        StringBuilder stringBuilder = new StringBuilder();
        System.out.println(">>>CustomSocketConnection, connectionEstablished, prima del while");

        try {
            InputStreamReader isr = new InputStreamReader(is, "UTF-8");
            System.out.println(">>>CustomSocketConnection, connectionEstablished, prima della read");

            while(true){
                System.out.println(">>>CustomSocketConnection, loop di read, inizio");
                int read = isr.read();
                System.out.println(">>>CustomSocketConnection, loop di read, subito dopo la read");
                char c = (char) read;
                if (read == -1) rawMessage = null;

                System.out.println(">>>CustomSocketConnection, loop di read, letto: " + c);

                while(c != termination){
                    stringBuilder.append(c);
                    read = isr.read();
                    c = (char) read;
                    if (read == -1) rawMessage = null;
                }
                rawMessage = stringBuilder.toString();
                if(rawMessage != null) doActions(rawMessage);

                //System.out.println(">>>CustomSocketConnection, connectionEstablished, ho letto: " + rawMessage + "FINE");
            }


        } 
        catch (IOException ex) {
            System.out.println(">>>CustomSocketConnection, connectionEstablished, errore: " + ex.getMessage());
        }

        System.out.println(">>>CustomSocketConnection, connectionEstablished, dopo il while"); 

    }

    private void doActions(String msg){
        //do something

    }
}

在 connectionEstablished 方法中，我使用InputStreamReader类的read方法从服务器读取数据。

如果我在模拟器上运行应用程序，它可以正常工作，并从服务器接收数据。当我在真实设备（iPad mini，32位设备，iOS版本8.1.1 12B435，more details here; iPhone 7s，64位设备，iOS版本11.2.5 15D60）上启动应用程序时，读取方法不会不接收来自服务器的数据。事实上，我可以在read方法之前看到println打印的字符串，但是在read方法之后我看不到println打印的字符串。

问题不在服务器端，因为我开发了一个Android应用程序，它从同一台服务器接收数据。没有防火墙限制或其他网络限制：Android应用程序和Codename One模拟器在服务器的同一本地网络或另一个网络上连接时都会接收数据。

怎么了？

Answer 1

使用InputStream而不是InputStreamReader解决。

@Override
public void connectionEstablished(InputStream is, OutputStream os) {
    System.out.println(">>>CustomSocketConnection, connectionEstablished");

    char termination = '\n';

    StringBuilder stringBuilder = new StringBuilder();
    System.out.println(">>>CustomSocketConnection, connectionEstablished, prima del while");

    try {
        System.out.println(">>>CustomSocketConnection, connectionEstablished, prima della read");

        while(true){
            System.out.println(">>>CustomSocketConnection, loop di read, inizio");
            int read = is.read();
            System.out.println(">>>CustomSocketConnection, loop di read, subito dopo la read");
            char c = (char) read;
            if (read == -1) rawMessage = null;

            System.out.println(">>>CustomSocketConnection, loop di read, letto: " + c);

            while(c != termination){
                stringBuilder.append(c);
                read = is.read();
                c = (char) read;
                if (read == -1) rawMessage = null;
            }
            rawMessage = stringBuilder.toString();
            if(rawMessage != null) doActions(rawMessage);

            //System.out.println(">>>CustomSocketConnection, connectionEstablished, ho letto: " + rawMessage + "FINE");
        }


    } 
    catch (IOException ex) {
        System.out.println(">>>CustomSocketConnection, connectionEstablished, errore: " + ex.getMessage());
    }

    System.out.println(">>>CustomSocketConnection, connectionEstablished, dopo il while"); 

}

任何人都可以解释为什么它与InputStream一起使用吗？

Codename One - 无法从真实设备上的套接字读取

1 个答案: